Horological pieces, such as watch-bracelets including a photovoltaic cell as an energy source, are already known. In these watches, the cell is generally located on the watch case or on the bracelet, at a location such that the cell may be exposed to sufficient luminous radiation to be able to assure the supply of current to the elements of the watch which function electrically.
The arrangement of the cell on the watch degrades its aesthetic appearance.
Further, this arrangement does not allow the photovoltaic cell to supply a sufficiently high voltage to assure the supply of current in all conditions of use, this being notably in conditions of weak lighting and of diffused light.